Final answer:
The key feature of anxiety disorder due to another medical condition is anxiety caused by a physiological condition. This type of anxiety can exacerbate issues like chronic insomnia and contribute to a cycle of increasing anxiety and sleep disturbances, making diagnosis and treatment crucial.
Step-by-step explanation:
The key feature of anxiety disorder due to another medical condition is c) Anxiety caused by a physiological condition. This is distinguished from other forms of anxiety that may be due to psychological factors, such as stress or trauma, as seen in post-traumatic stress disorder (PTSD). The anxiety linked with medical conditions can lead to or exacerbate issues such as chronic insomnia, which may contribute to depression symptoms and further increase anxiety levels—a feedback loop that can be particularly challenging to break.
A range of medical conditions can underlie anxiety disorders, such as cardiovascular diseases, where patients with stable coronary heart disease may experience increased anxiety and subsequent cardiovascular events. In the realm of sleep disturbances, there are conditions like night terrors and sleep apnea that can cause significant stress and anxiety due to their direct impact on the quality of sleep.
Proper diagnosis and treatment are crucial as the physiological basis of the anxiety needs addressing alongside the psychological symptoms. This holistic approach aims to improve both the underlying medical condition and the anxiety it causes, leading to an improved overall quality of life for the affected individuals.